SRW with 36' gooseneck

Ok, I have read a lot about this set up but i feel every situation is unique.

I will be traveling from Birmingham to Manheim Pa 2-3 times each month. I buy 10-15 cars each week and I'm looking to reduce costs by taking 2 up and 2 (inops) back home to sell. I also will be going to Atlanta and Nashville regularly. and finally, I will be using it locally to deliver and pick up cars around town.

1) will this actually save money? (currently I pay $400 a car from PA)
2) is a GN out of the question or is a bumper pull better (36 feet)?
3) is a Appalachian (14000 GVW and 4500 lbs) a decent trailer or what opinions do ya'll have for something around $7500
4) Is this safe?

I know what to do with regards to a medical card and DOT number. I want to avoid a CDL for now and loading 2 cars is relatively easy. The reason I am using the F250 is because its an easy truck to re-sell and I know I can get my money back even with adding 40k.